It's simply not that hard to raise food animals in a way that makes them better off than wild animals

And yet it's extraordinarily difficult to actually find meat from animals that were raised truly humanely. See this comment.

Also, I think the standard one should apply is whether an animal has a good life, not whether it as a life better than it would if it were in the wild. If you have a life that is very not worth living, it would better to not exist than to move up to having a life that is only moderately not worth living.

Ninjaedit: Actually, I think I misunderstood your point about farm animals having lives better than wild animals. Are you saying that it's worth it to have non-factory-farmed farm animals when their lives are better than those of comparable wild animals, because they displace the existence of those wild animals?